1. Field of the Invention
The present invention relates to an image reading method and an image reading device, and in particular, to an image reading method and an image reading device which read an image recorded on a photographic photosensitive material such as a photographic film or the like.
2. Description of the Related Art
Among conventional laboratory systems which process images recorded on a photographic photosensitive material such as a photographic film or the like (hereinafter simply referred to as "film"), there are laboratory systems structured as follows. First, preliminary reading (hereinafter, prescanning) is conducted in which the images are read at a relatively high speed and relatively roughly. On the basis of the image data obtained by prescanning, photometric conditions, for the time that main reading (hereinafter, fine scanning) is carried out to read the images at a relatively low speed and in relatively great detail, and processing conditions, for image processing to be carried out on the image data obtained by the fine scanning, are determined. Fine scanning is carried out on the basis of the determined photometric conditions, and image processing is carried out under the determined processing conditions on the image data obtained by fine scanning.
In this type of laboratory system, an image reading device used to read images recorded on a film may include two photometric systems equipped with CCD sensors for reading the images, in order to accelerate the image reading processing. Prescanning and fine scanning are carried out at the respectively different photometric systems, so as to be carried out in parallel.
Recently, there has been demand for so-called large-scale reading in which a large number of films are continuously read in order to improve the processing capability.
Generally, in order to efficiently read a large number of developed films, there is proposed a system in which end portions of respective films are connected together by splicing tape or the like to form an elongated film, and this elongated film is continuously read while being conveyed by a conveying device such as conveying rollers or the like. Further, there has been proposed, as another method, a method in which long ends (ends in which perforations are formed) of plural piece films which have been cut per plural frames are adhered to an elongated tab, so as to form an elongated form.
However, when an elongated film in which films are connected together by splicing tape or the like is conveyed, there is a drawback in that a connected portion thereof may catch on conveying rollers and the connected portion and the conveying rollers may interfere with each other so as to change the speed of the conveying rollers, which changes the conveying speed of the film. If the conveying speed of the film changes while an image frame is being read, a problem arises in that satisfactory reading cannot be carried out.
Further, when a film which includes deformed perforations is conveyed, the deformed perforations may catch on the conveying rollers and the deformed perforations and the conveying rollers may interfere with each other so as to change the conveying speed of the conveying rollers, which slows down the conveying speed of the film. Thus, when a film including deformed perforations is conveyed, a problem arises in that satisfactory reading cannot be carried out.